@@ -459,6 +459,20 @@ void vu_queue_notify(VuDev *dev, VuVirtq *vq);
*/
void *vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz);
+
+/**
+ * vu_queue_unpop:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @elem: The #VuVirtqElement
+ * @len: number of bytes written
+ *
+ * Pretend the most recent element wasn't popped from the virtqueue. The next
+ * call to vu_queue_pop() will refetch the element.
+ */
+void vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+ size_t len);
+
/**
* vu_queue_rewind:
* @dev: a VuDev context
@@ -1966,6 +1966,22 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz)
return elem;
}
+static void
+vu_queue_detach_element(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+ size_t len)
+{
+ vq->inuse--;
+ /* unmap, when DMA support is added */
+}
+
+void
+vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+ size_t len)
+{
+ vq->last_avail_idx--;
+ vu_queue_detach_element(dev, vq, elem, len);
+}
+
bool
vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num)
{
vhost-user-input will make use of this function to undo some queue pop in case the virtio queue does not have enough room. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> --- contrib/libvhost-user/libvhost-user.h | 14 ++++++++++++++ contrib/libvhost-user/libvhost-user.c | 16 ++++++++++++++++ 2 files changed, 30 insertions(+)